RASPBERRY VIRUSES IN OREGON, WASHINGTON AND BRITISH COLUMBIA

A survey of viruses in raspberry production fields was undertaken, and leaflets were collected from 72 plants per field in Oregon, Washington and British Columbia. Leaflets were collected from three or four rows in each field spaced to give a representative sampling of the field. Cultivar and age of plantings were noted. Three leaflets were pooled to make a single sample, thus 24 individual samples (72 leaflets) were tested per field by ELISA. Each sample was tested in duplicate for rasbperry bushy dwarf (RBDV), tomato ringspot (ToRSV) and tobacco streak (TSV) viruses. Known infected raspberry plants maintained in a greenhouse were used as positive controls in all of the tests. In the Fraser Valley (northwestern Washington and southwestern British Columbia), RBDV was widespread (32/38 fields had RBDV) and occurred at a high incidence within fields (24/32 fields had greater than 50% infection rate). The six fields that did not have RBDV in this area were less than two years old. ToRSV and TSV were not found in the Fraser Valley. In southern Washington and Oregon, TSV, ToRSV and RBDV were all found sporadically in red raspberry. In this area, RBDV, TSV and ToRSV occurred in 9/55, 8/55 and 14/55 fields, respectively. None of the fields in this area had RBDV infection rates over 50%. In black raspberry (Rubus occidentalis) fields in Oregon both RBDV and TSV were found commonly at infection rates greater than 50%. However, RBDV and TSV were not found in native R. leucodermis plants adjacent to black raspberry fields with high levels of RBDV and TSV infections